Cat emoji as its ticker symbol, one hundred million units at two decimals.
Historical Significance
The ticker is a single cat face emoji, stored on chain as UTF-8 bytes at a time when almost every token used plain ASCII letters. The issuer named at deployment holds the whole opening supply and alone can mint further units or freeze an address, after which transfers from it are rejected. Holders have no approval or allowance mechanism.
Context
Deployed in December 2015 during the Frontier era.
Token Information
Key Facts
Description
The ticker is a single cat face emoji, stored on chain as UTF-8 bytes at a time when almost every token used plain ASCII letters. The issuer named at deployment holds the whole opening supply and alone can mint further units or freeze an address, after which transfers from it are rejected. Holders have no approval or allowance mechanism.
Source Verified
Exact bytecode match. Runtime 1,093 bytes. Creation 1,582 bytes plus 288 bytes of ABI-encoded constructor arguments (initialSupply=100000000, tokenName="CatCoin", decimalUnits=2, tokenSymbol="๐ฑ", centralMinter=0x18EBd42Dc5E42EDaC84e8DEd1dc824Af20008564). The compiler is pinned to the Solidity 0.1.x line by the identity-precompile gas formula in the string-return helper: this contract emits words*3+15 (600302600f01), while 0.2.0 and later emit words*15+3. Both 0.1.5 and 0.1.6 reproduce the deployed bytecode exactly; 0.1.3 and 0.1.4 produce 1,059 bytes. Optimizer on. The source is a trimmed ethereum.org MyAdvancedToken with owner renamed to issuer and the allowance functions removed. This contract cannot be verified on Etherscan or Sourcify. solc 0.1.x emits two valid, semantically identical code layouts for this source depending on emscripten heap state: the shared string-copy block used by the name() and symbol() getters sits either before the function bodies (fresh compiler) or at the end of the contract (warm compiler). The deployed contract uses the warm-module layout, which is what browser-solidity produces because it recompiles on every keystroke. Etherscan and Sourcify each compile once in a clean process and land on the other layout. Sourcify does accept solc 0.1.4 through 0.1.7 and compiles this source successfully, but returns no_match. The script proofs/catcoin-0x8e72a683/verify.js in awesome-ethereum-proofs warms the compiler and reproduces the match byte for byte.
Historian Categories
Heuristic Analysis
The following characteristics were detected through bytecode analysis and may not be accurate.
Frontier Era
The initial release of Ethereum. A bare-bones implementation for technical users.
Bytecode Overview
Verified Source Available
Source verified through compiler archaeology and exact bytecode matching.
View Verification ProofShow source code (Solidity)
// Submitted by EthereumHistory (ethereumhistory.com)
contract MyToken {
string public name;
string public symbol;
uint8 public decimals;
address public issuer;
mapping (address => uint256) public balanceOf;
mapping (address => bool) public frozenAccount;
event Transfer(address indexed from, address indexed to, uint256 value);
event FrozenFunds(address target, bool frozen);
modifier onlyOwner { if (msg.sender != issuer) throw; _ }
function MyToken(uint256 initialSupply, string tokenName, uint8 decimalUnits, string tokenSymbol, address centralMinter) {
if (initialSupply == 0) initialSupply = 1000000;
if (centralMinter == 0) centralMinter = msg.sender;
issuer = centralMinter;
balanceOf[centralMinter] = initialSupply;
name = tokenName;
symbol = tokenSymbol;
decimals = decimalUnits;
}
function freezeAccount(address target, bool freeze) onlyOwner {
frozenAccount[target] = freeze;
FrozenFunds(target, freeze);
}
function mintToken(address target, uint256 mintedAmount) onlyOwner {
balanceOf[target] += mintedAmount;
Transfer(0, target, mintedAmount);
}
function transfer(address _to, uint256 _value) {
if (balanceOf[msg.sender] < _value || balanceOf[_to] + _value < balanceOf[_to] || frozenAccount[msg.sender]) throw;
balanceOf[msg.sender] -= _value;
balanceOf[_to] += _value;
Transfer(msg.sender, _to, _value);
}
}External Links
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